While pyrotechnics may be imagined and installed by human beings, the design and execution of the Space Needle’s New Year’s fireworks extravaganza in Seattle spends most of its life inside a computer.
Well ahead of the New Year’s show, Alberto Navarro, the architect of the annual New Year’s at the Needle fireworks show, enhances his libraries of computer-represented effects with the models of the latest pyrotechnic technology. Sometime around September, he receives the playlist of music for the next Space Needle show from radio station KEXP-FM.
Navarro, the owner and lead designer of Bellevue, Wash.’s Infinity Visions, negotiates a bit with the KEXP team after receiving the suggested soundtrack of the show, but they quickly converge on the set list. This is crucial because the beats, riffs and emotions contained in the songs drive the flow, the rhythm and the punctuations that transform what is essentially a playlist into a visual spectacular. Navarro starts painting in his mind with ball rockets, blinkers, comets, crackling crossettes, kamuros and spirals as soon as he starts hearing the music.
When Navarro first started planning shows, he was doing so with a visual handicap: he couldn’t actually see what his mind could imagine until the show actually took place. In 1995, he used a physical model of the Space Needle, and did lot of jotting and entering of information into spreadsheets. Then, in 1997, he created the Show Director choreography software to synchronize music contained in a .WAV file, with a table of events — things like “where, and what, what angles, and how many, at what time, etc.”
Then Navarro got really inspired. “In 2001, we developed Visual Show Director, the first 3D realtime simulation software for pyrotechnics,” he explains. “It also does laser and light simulation, along with object animation. This started to change shows because you could visualize what you are doing.”
Visual Show Director is also a particle simulator, which means it includes a sophisticated physics engine to simulate not only how the projectiles will fly and where they will explode, but the results of the burning chemicals as they become a shape or pattern.
No longer must Navarro close his eyes, listen to a playlist and attempt to remember and imagine each and every effect and launch and the timing. The computer remembers everything — showing the ultimate visual expression of black powder, potassium chlorate, potassium perchlorate, sulfur, aluminum, charcoal, dextrin, red gum, iron, sodium, copper, strontium carbonate, barium nitrate or barium chlorate as they ignite and burn into beautiful spirals, flowers and cascades against the hopefully black and breezy sky over Seattle Center.
With simulation software, he can create the show incrementally, test out various portions in the simulator, and refine them.
“The creative process is enriched by the software,” he says. “It allows us to streamline the show. We can make it so there is no more than needed. Of course, less isn’t always more, sometimes more is better, but it allows us to be economical, to not just jump to effects because we can. It also allows the producer to see what needs to be set and done.”
Like painting the sky
Navarro relies on pre-configured libraries of firework types that be referenced in the model. They are all objects that include simulation characteristics like the duration, colors, and different behaviors.
“The show is 100 percent simulated,” he said. “Software allows ‘what you see is what you get.’ Fireworks isn’t always exact. But with the software, it is like painting, you can see every brush stroke, how it goes with previous ones, and how it mixes. In the past, all we could see was a list of effects with the sound playing. Now we can highlight that list and see how the various effects look, say, from the Key Arena, Downtown, or from the Science Center. Even a helicopter view. If I don’t use visualization, I’m kind of blind.”
Remember, Navarro says, “this is a musical show. If you just look at the show without the music, it isn’t the same. I recommend that you have at least a radio so you can understand the choreography of the fireworks.”
Once the design is complete, Navarro continues, “The software produces a script and plans, and then they build it. The rest is the performance of the show, which is pretty spectacular.”
That’s when the team at Pyro Spectaculars takes over. They receive a Show Director spreadsheet that strips out all the superfluous information. “All you need is time and address, the circuit,” says Pyro’s Jon Berson. They plan around a series of triggering boxes, each of which has sixteen circuits. The first two digits are the box number, followed by a hexadecimal address.
A controller runs everything on a 24-volt, 3-wire set-up using an XLR cable, like the one you might find in a stage microphone. Firing is derived from a precisely timed differential in the voltage.
Berson says, “It’s pretty low-end technology. A basic microprocessor, running down a list of actions and opening gates on the appropriate module at the appropriate time, to initiate an event.” Hardware from Pyrodigital keeps the show running smoothly, including pre-show quality control that identifies open circuits and other faults.
The physical side is the real challenge for Berson and his team. “we have to manufacture and load individual props. Depending on the complexity of the show, and he [Navarro] is a rather complex designer, so we are also dealing with a 360-degree space. Props tend to be pretty complex.”
Because of tight timeframes — Berson and his team started fabricating in mid-November and finished on Dec. 18 — they too use software to help both visualize and expedite their work. Berson tends to use Microsoft Visio to “create a fundamental rendering of what we are trying to do.” It takes about 3 days to install the show. The Space Needle has 185 props mounted on it, some with 30 or 40 devices in them.
Berson explains, “It is a 360-degree space. Any given piece is going to have a tilt angle of 45, with a pan angle of 330. That may be the only piece like that, so you have to figure out where on the prop you can put that so it won’t get in the way of other device you are trying to put on the prop. For me, a lot of it is space planning to make sure I can fit what I want to fit, in a device that can be picked up, and it will fit through the hatch it has to fit through, and actually be put on a truck. All of those logistical and operational concerns.”
3D modeling software, SketchUp, can also play a role. Berson says, “It allows for searching and importing models of objects. It’s even linked to Google Earth so you can pull up a 3D rendering and object and get to know it. Zoom in and see how many pieces of railing there are on the upper roof. Oh, twelve segments. I get it.”
A 3D model of the Space Needle now exists in virtual space, complete with its various attachment points for projectiles and other effects. These are the locations where the team at Pyro Spectaculars will eventually rappel down to plant their charges. For now it is the working space for Navarro to plant virtual versions of various fireworks from a library he has built over time.
The Space Needle presents unique challenges to fireworks designers. Unlike many shows that start and end on a flat platform, or execute in a constrained plane, “we have to play with the Space Needle, Navarro says, “which is a three-dimensional structure and show. It will be seen in 360 degrees around. That is kind of unique because you can see fireworks from anywhere, but they still display with a kind of front. With the Space Needle you have to think about people seeing it from all points of view.”
3D models become real
Navarro isn’t satisfied with the status quo. He sees 3D printing as one of the technologies that will help turn new ideas into reality. He has owned a 3D printer for four years. He can visualize a mount, for instance, design it, and then print it as a prototype. The final units will still require the team at Pyro Spectaculars or another partner to transform the prototype into a series of them production units, but 3D will take much of the guesswork out of the design process.
“We have to keep making the show better, to differentiate it from the previous years,” Navarro says. “There are always new prop ideas that will create new patterns and graphics — with the supports with CNC machining that will allow us to do a very different show, with new patterns, with a different visual language.”
3D printing will be very important for “projectiles and cartridges for projectiles that have a special ballistics,” he explains. “Especially for new pattern technology that is coming. Particularly for shows in places like Dubai that have more resources. Also the propping. I 3D-print the props to show the direction of all the holes.”
Berson sees other changes, as well: “The chemistry is always evolving, the materials are getting cheaper and we are trying, as an industry, to create devices that generate less smoke.” These changes will help create safer indoor, or proximity shows, which may well mean seeing fireworks more often in the future.
If you have a child who isn’t that into science, perhaps the fireworks show will encourage him or her to connect science to something fun and real. The fireworks show requires geometry, chemistry, physics and engineering, and the show lives in software — so that it can be designed, planned, manufactured and installed — for a much longer time than it will exist in the real world. With tools like Navarro’s Visual Show Director, though, shows can be relived, even recreated, because of the data still exist, and the compiled simulation output as a video makes it possible to replay the show any time. See last year’s show here:
In the end though, a fireworks display is a social event. Despite all of the power of software and simulation, Navarro says, “The important thing is that people have to go there. It is a party. And there is nothing like seeing the show done there at the Needle. It can’t match TV. It’s real and the presence of the Space Needle, the structure, is magic. I encourage people to go down and visit it in person.”
Fireworks: Chemistry behind the scenes
Ever wonder about the science behind your favorite fireworks? Here’s how it works.
A leader fuse attaches to each projectile cylinder in a prop. Sometimes several projectiles are wired together so that a single signal sets off the bundle. The leader fuse leads into at least two fuses within the cylinder. The first burns quickly and lifts the projectile to its specified height. The second, known as the break charge, explodes the projectile, revealing the hidden pattern within the shell, which is expressed as “stars” — it is the profusion of stars that captivate audiences.
Color is produced by chemistry. When a chemical like barium chlorate heats, its electrons get excited. As they cool, they give off energy, which is emitted in a particular frequency that can be seen by the human eye. In this case, green. Barium, combined with red gum, creates a lethal combination of oxidizer and fuel. Dextrine rounds out the chemical cocktail as the binder.
All of these chemicals are sifted into a very fine powder, mixed together, and eventually mixed with water, to create dough that becomes loaf. Pieces of the loaf become individual stars. Black powder coats all the “stars” so they are more likely to ignite. There is no metal in this process, so that those crafting the fireworks don’t inadvertently create a spark, resulting in their entire workspace blowing up.
Some fireworks use nitrocellulose as a fuel, because it is fast burning, and smokes less that other chemical combinations. Nitrocellulose substance is employed by magicians to create a real, but safe, fire flash on stage.
The big booms that catch spectators’ attentions aren’t by-products of firework explosions, but are themselves engineered and the boom is as precisely timed as the pyrotechnic glitter. The booms are know as “salutes.” They consist of explosive chemicals packed in shells of much higher density so more pressure is built up before they explode — thus, the boom. Other sounds, like crackles, are created with metal flakes, in which whistles emanate from holes drilled into projectiles. Sounds allow spectators to “feel the show.”
For height and diameter of explosion, it is all about size. Think 100 feet per inch of shell. A 5-inch shell will fly up about 500 feet and explode into a 500 foot pattern. Space Needle pyrotechnics, however, are significantly smaller, in the 1.5 to 2 inch range.